Carcinoembryonic antigen, CA 19-9, and CA 125 in normal and carcinomatous human colorectal tissue.

In 115 primary colorectal carcinomas and 64 normal colorectal mucosa specimens the concentrations of carcinoembryonic antigen (CEA), CA 19-9, and CA 125 were measured. The determinations were performed in cytosols by use of radioimmunometric and enzymeimmunometric assays and related to the wet tissue weight. In the cancer tissue the CEA levels ranged from 5.5 to 1990 micrograms/g tissue and were significantly higher (P less than 0.0001) than those found in the normal mucosa (1.2-58.6 micrograms/g). The CA 19-9 content in carcinoma specimens (120-72660 U/g) was also significantly higher (P = 0.011) than in the normal mucosa (37-5800 U/g). In contrast, no significant difference of the CA 125 concentrations between the normal and the cancer tissue was found. The relative operating characteristic (ROC) curves for the three markers corroborate CEA as the marker superior to CA 19-9. On the other hand is shown that CA 125 is completely unable to discriminate between normal and cancer tissues. A decreasing CEA tissue concentration and an increasing dedifferentiation of colorectal cancers were significantly (P = 0.018) related with each other. Higher tumor stages implied significantly higher tissue marker values of CA 19-9 (P = 0.027) and CA 125 (P = 0.0008). The findings correspond quite well with serum examinations of the three markers which have been reported earlier.